Process of braking triflouromethyl compounds

ABSTRACT

A process for the preparation of trifluoromethylvinyl compounds in all their possible streoisomeric forms and mixtures thereof comprising reacting a salt of trifluoroacetic acid with a halovinyl compound in the presence of a cuprous salt to obtain the same stereo-specific compound and all possible stereo-isomeric forms and mixtures thereof of 1R, trans compounds of the formula ##STR1## wherein R is an alcohol residue used in pyrethrinoid series, or an alcohol residue capable of blocking the acid function, and Z is aryl or haloaryl and the double bond has Z geometry having pesticide activity.

STATE OF THE ART

Related prior art compounds are disclosed in British Pat. No. 2,034,700,U.S. Pat. Nos. 4,737,513; No. 4,551,281; No. 4,344,963; No. 4,485,252;No. 4,491,585; No. 4,582,921 and No. 4,650,887 and Chemistry Letters,No. 12, Dec. 1981, pp. 1719-20.

OBJECTS OF THE INVENTION

It is an object of the invention to provide a novel process forpreparing trifluorovinyl compounds from the corresponding halovinylcompounds.

It is another object of the invention to provide the novel cyclopropanecarboxylates of formula I.

It is a further object of the invention to provide novel pesticidalcompositions and a novel method of combatting pests.

These and other objects and advantages of the invention will be obviousfrom the following detailed description.

THE INVENTION

The novel process of the invention for the preparation oftrifluoromethylvinyl compounds in all their possible stereoisomericforms and mixtures thereof comprises reacting a salt of trifluoroaceticacid with a halovinyl compound in the presence of a cuprous salt toobtain the same stereo-specific trifluoromethylvinyl compound.

The process of the invention has the advantage of preserving thestereo-specificity of the halovinyl starting products. If the geometryof the double bond of the halovinyl product used is E, the geometry ofthe trifluoromethyl product is E and if the geometry of the double bondof the halovinyl product is Z, the geometry of the trifluoromethylvinylproduct is Z. Preferably, the trifluoroacetic acid salt used is sodiumtrifluoroacetate and the cuprous salt used is cuprous iodide.

The process of the invention allows the preparation of numeroustrifluoromethylvinyl products and especially certain derivatives of2,2-dimethyl-cyclopropane carboxylic acid.

More particularly, the subject of the invention is a process for thepreparation of the products of formula I ##STR2## in all their possiblestereoisomeric forms and mixtures thereof wherein R is an alcoholresidue used in pyrethrinoid series, or an alcohol residue capable ofblocking the acid function, and Z is an electro-attracting groupcharacterized in that a product of the formula ##STR3## in all theirpossible stereoisomeric forms and mixtures thereof wherein Z and R havethe above meaning and Hal is bromine, chlorine or iodine is reacted withsodium trifluoroacetate in the presence of cuprous iodide to obtain thecorresponding product of formula I.

The process is totally stereospecific with the geometry of the doublebond and the structure of the cyclopropane moiety of the productsobtained being the same as the starting products.

In a preferred method, Hal is bromine and more particularly, Z is aryloptionally substituted by a halogen such as, for example, phenylsubstituted by a 4-chlorine.

In another preferred embodiment, Z is --COOR' and R' is alkyl of 1 to 8carbon atoms. Examples of R' are methyl, ethyl, n-propyl and isopropyl.In a further preferred embodiment, R is alkyl of 1 to 8 carbon atomsoptionally substituted with trialkylsilyl, preferably alkyl of 1 to 4carbon atoms substituted with trimethylsilyl or benzyl optionallysubstituted with at least one member of the group consisting of alkyl of1 to 4 carbon atoms, alkenyl and alkenyloxy of 2 to 6 carbon atoms,alkadienyl of 4 to 8 carbon atoms, halogen and methylenedioxy.

R may also be (a) a group of the formula ##STR4## wherein R₁ is hydrogenor methyl and R₂ is monocyclic aryl or --C.tbd.CH, (b) or a group##STR5## in which a is hydrogen or methyl and R₃ is an aliphatic organicof 2 to 6 carbon atoms having one or more carbon-carbon unsaturations,especially --CH₂ --CH═CH₂, --CH₂ C.tbd.CH, --CH₂ CH═CH--CH₃, --CH₂--CH═CH--CH═CH₂, or --CH₂ --CH═CH--CH₂ --CH₃, (c) or a group ##STR6## inwhich a is hydrogen or methyl, R₃ has the above definition, R₁ ' and R₂' are individually hydrogen, halogen, alkyl of 1 to 6 carbon atoms, arylof 6 to 10 carbon atoms, alkoxycarbonyl of 2 to 5 carbon atoms, orcyano, (d) or a group ##STR7## in which B is oxygen or sulfur, ##STR8##or --CH₂ -- or a sulfoxide or a sulfone and R₄ is hydrogen, --C.tbd.N,methyl, --CONH₂, --CSNH₂ or --C.tbd.CH, R₅ is halogen or methyl and n is0, 1 or 2, (e) or a group ##STR9## (f) or a group ##STR10## in which R₆,R₇, R₈, R₉ are hydrogen, chlorine, or methyl and which S/I symbolizes anaromatic ring or a dihydro or tetrahydro ring, (g) or a group ##STR11##(h) or a group ##STR12## in which R₁₀ is hydrogen or --CN, R₁₂ is --CH₂-- or oxygen, R₁₁ is thiazolediyl or thiadiazolediyl in which the bondwith

can be found in any of the positions available, R₁₂ is linked to R₁₁ bythe carbon contained between the sulfur atom and the nitrogen, (i) or agroup ##STR13## (j) or a group ##STR14## in which R₁₃ is hydrogen or--CN, (k) or a group ##STR15## in which R₁₃ is defined as above, and thebenzoyl radical is in position 3 or 4, (l) or a group ##STR16## in whichone of R₂ " or R₃ " is ##STR17## Z is hydrogen, --C.tbd.N, --C.tbd.CH,--CF₃ or alkyl of 1 to 3 carbon atoms and the other R₂ " or R₃ " and R₄' and R₅ ' are individually hydrogen, halogen, alkyl of 1 to 18 carbonatoms, aryl of 6 to 14 carbon atoms, arylalkyl of 7 to 18 carbon atoms,cyano, --CF₃, alkoxycarbonyl of 2 to 8 carbon atoms, NO₂, alkyloxy of 1to 8 carbon atoms, ##STR18## n being 0, 1 or 2 and the radicals Ra, Ra₁and Ra₂ are alkyl of 1 to 8 carbon atoms, Rb is either ##STR19## inwhich X and Y are individually hydrogen, halogen, alkyl of 1 to 8 carbonatoms or aryl of 6 to 14 carbon atoms or ##STR20## radical in which X',Y' and Y" are individually one of the values indicated above for X andY, the dotted line representing a possible double bond between thecarbons 1 and 2;

(m) or ##STR21## in which r' can have the values indicated previouslyfor R₄ " and R₅ " with the exception of halogen, cyano, --NO₂, ##STR22##in which n is either 1 or 2 and ##STR23## (n) or ##STR24## in which R"and R"' are individually hydrogen, alkyl of 1 to 18 carbon atoms, arylof 6 to 14 carbon atoms, aralkyl of 7 to 18 carbon atoms, --CF₃,alkoxycarbonyl of 2 to 8 carbon atoms or alkoxy of 1 to 8 carbon atoms,

(o) or a group ##STR25## in which R₁₄ is hydrogen, methyl, ethynyl orcyano and R₁₅ and R₁₆ are individually hydrogen, fluorine or bromine,(p) or a group ##STR26## in which R₁₄ is defined as above, each of theR₁₇ 's independently is alkyl of 1 to 4 carbon atoms, alkoxy of 1 to 4carbon atoms, alkylthio of 1 to 4 carbon atoms, alkylsulfonyl of 1 to 4carbon atoms, trifluoromethyl, 3,4-methylenedioxy, chloro, fluoro orbromo, p is an integer 0, 1 or 2 and B' is oxygen or sulfur.

The process of the invention permits the preparation of products, whichare very useful as pesticides, as well as intermediates useful in thesynthesis of these products such as certain products of the EuropeanPat. No. 0,019,787. It also allows the preparation of new products and asubject of the invention is also these new products, namely methyl[1R-(1α, 3β)]2,2-dimethyl-3-[(ΔZ)-2-(4-chlorophenyl)-3,3,3-trifluoro-1-propenyl]-cyclopropanecarboxylate and 2-(trimethylsilyl) ethyl [1R-(1α,3β)]2,2-dimethyl-3-[(ΔZ)-2-(4-chlorophenyl)-3,3,3-trifluoro-1-propenyl]-cyclopropanecarboxylate.

Also an object of the invention are the products of the formula##STR27## in which the cyclopropane moiety is of 1R trans structure, thegeometry of the double bond is Z, Z₁ is aryl or alkyl substituted by ahalogen, and X is hydrogen, or fluorine, and notably the product of thestructure ##STR28##

Also the products of formula I in all their possible stereoisomericforms and mixtures thereof of the formula ##STR29## in which Z₁ and R₁₄have the same meaning as previously, and especially those in which R₁₄is methyl, or those in which Z₁ is ##STR30## and especially the productsof the formula B₁ : ##STR31## in all their possible stereoisomeric formsas well as mixtures thereof.

As indicated several times, one of the advantages of the process of theinvention is that it is stereospecific, especially for the compounds inwhich the cyclopropane moiety is of 1R, trans structure and the geometryof the double bond is Z.

The novel pesticidal composition of the invention are comprised of apesticidally effective amount of at least one compound of formula I andan inert carrier. The compositions are useful to combat pests such asparasites of vegetables and of warm-blooded animals such as cattle,sheep and fowl as well as parasites of premises and are particularlyuseful to combat insects, nematodes and parasitic acariens which attackwarm-blooded animals and vegetables.

The compositions of the invention are particularly useful to combatinsects in the agricultural field, for example, to control aphides andlarvae of lepidoptera and coleoptera and are usually used at a dose of10 to 300 g of the compounds of formula I per hectare. The compositionsare also useful to combat insects in the premises for example to combatflies, mosquitoes and beetles. The insecticidal compositions of theinvention are particularly preferred and may contain 0.005 to 10% byweight of the active ingredient.

In the advantageous operation for use in premises, the compositions arein the form of fumigants. These compositions advantageously have fortheir inactive portion a combustible serpentine or coil base or anincombustible fibrous substrate. In the latter case, the fumigantobtained after incorporation of the active ingredient of formula I isplaced in a heating apparatus such as an electromosquitoe destroyer. Theusual active dose in this case is 0.03 to 95% by weight, preferably.

In the case of a serpentine insecticide, the inert support may be made,for example, of pyrethrum marc, Tabu powder (or Machilus Thumbergii leafpowder), powder of pyrethrum stems, cedar needle powder, sawdust such aspine sawdust, starch and powder of coconut shells. The active dose inthis case is preferably 0.03 to 1% by weight.

The compositions of the invention for premise use may be prepared as aspraying oil containing the active ingredient and the oil may soak thewick of a lamp which is then subjected to combustion. The concentrationof the active compound in the oil is preferably 0.03 to 95% by weight.

The compositions of the invention are also useful to combat acariens andnematode parasites of vegetables containing at least one compound offormula A as the active ingredient and they may be in the form ofpowders, granules, suspensions, emulsions or solutions.

For acaricide use, the compositions are preferably wettable powders forfoliar spraying containing 1 to 80% of the active ingredient or liquidsfor foliar spraying containing 1 to 500 g/l of the active ingredient.Also useful are powders for foliar powdering containing 0.05 to 3% byweight of the active ingredient. For nematocide use, the compositionsare in the form of liquids for soil treatment containing 300 to 500 g/lof the active ingredient. For acaricide and nematocide use, thepreferred dose of the active compounds is 1 to 100 g per hectare.

The compositions may also contain one or more other pesticidal agents.The compositions may be in the form of powders, granules, suspensions,emulsions, solutions, aerosol solutions, combustible bands, baits andother preparations classically used for compounds of this type.

Besides the active ingredient, the compositions generally contain avehicle and/or a nonionic surface active agent to ensure a uniformdispersion of the substances in the mixture. The vehicle used may beliquid such as water, alcohol, hydrocarbons or other organic solvents ora mineral, animal or vegetable oil or a powder such as talc, clays,silicates or Kieselguhr or a combustible solid.

The compositions of the invention are also useful to combat acarienparasites of warm-blooded animals such as ticks, especially ticks ofBoophilus species, Hyalomnia species, Amblyomnia species andRhipicephalus species and to combat all sorts of scabies such assarcoptic scabies, psoroptic scabies and chorioptic scabies. They canalso be useful to combat lice and helminthes. The invention alsoincludes compositions intended to combat parasites of warm-bloodedanimals, especially ticks and gales, containing at least one compound offormula I.

The said compounds may be administered externally by vaporization, byshampooing, by painting or by bathing. For veterinary usage, thecompositions may also be administered by painting the dorsal spine bythe "pour on" method. When the "pour on" method is used, it is preferredto use solutions containing from 0.5 to 5 g of active material per 100ml of solution.

When the compositions are to be used to combat parasitic acariens ofanimals, the active compounds of formula I are very often incorporatedinto alimentary compositions in association with a nutritive mixtureadapted to the animal to be fed. The nutritive mixture will varydepending upon the species of animal but usually contains cereals,sugars and grains, soybean press cake, peanuts and turnsole press cake,meal of animal origin such as fish meal, synthetic amino acids, mineralsalts, vitamins and antioxidants.

Another feature of the invention are insecticidal, acaricidal ornemataocidal compositions containing as an active ingredient at leastone compound of formula I and as a second active ingredient at least onepyrethrinoid ester selected from the group consisting of esters ofallethrolone, of 3,4,5,6-tetrahydrophthalimido-methyl alcohol, of5-benzyl-3-furyl-methyl alcohol, of 3-phenoxy-benzyl alcohol andα-cyano-3-phenoxy-benzyl alcohols with chrysanthemic acids, esters of5-benzyl-3-furyl-methyl alcohol with2,2-dimethyl-3-(2-oxo-3-tetrahydrothiophenylidenemethyl)-cyclopropane-1-caraboxylic acids, esters of 3-phenoxy-benzylalcohol and α-cyano-3-phenoxy-benzyl alcohols with2,2-dimethyl-3-(2,2-dichlorovinyl)-cyclopropane-1-carboxylic acids,esters of α-cyano-3-phenoxy-benzyl alcohols with2,2-dimethyl-3-(2,2-dibromovinyl)-cyclopropane-1-carboxylic acids,esters of 3-phenoxy-benzyl alcohol with2-p-chloro-phenyl-2-isopropyl-acetic acids, esters of allethrolone,3,4,5,6-tetrahydrophthalimido-methyl alcohol, 5-benzyl-3-furyl-methylalcohols, 3-phenoxy-benzyl alcohol or α-cyano-3-phenoxy-benzyl alcoholswith 2,2-dimethyl-3-(1,2,2,2-tetrahaloethyl)-cyclopropane-1-carboxylicacids where halo is fluorine, chlorine or bromine wherein the compoundsof formula I and the above pyrethrinoid esters are in all possiblestereoisomeric forms.

To increase the biological activity of the compositions of theinvention, classical synergists may be incorporated therein such as1-(2,5,8-trioxadodecyl)-2-propyl-4,5-methylenedioxy-benzene (piperonylbutoxide) orN-(2-ethyl-heptyl)-bicyclo-[2,2-1]-5-heptene-2,3-dicarboximide orpiperonyl-bis-2-(2'-n-butoxy-ethoxy)-ethyl acetal (tropital).

The novel method of the invention for combatting parasites such asinsects, nematodes and acariens comprises contacting the parasites witha pesticidally effective amount of at least one compound of formula A.

In the following examples there are described several preferredembodiments to illustrate the invention. However, it is to be understoodthat the invention is not intended to be limited to the specificembodiments.

EXAMPLE 1 Methyl[1R-(1α,3β)]-2,2-dimethyl-3-[(ΔZ)-2-(4-chlorophenyl-3,3,3-trifluoro-1-propenyl]-cyclopropanecarboxylate STEP A: Methyl [1R-(1α,3β)]-2,2-dimethyl-3-[(ΔZ)-2-bromo-2-(4-chlorophenyl)-ethenyl]cyclopropane carboxylate and its 1R-[1α, 3β(ΔE)] isomer

7.8 g of methyl (1R, trans) 3-formyl-2,2-dimethyl-cyclopropanecarboxylate and 17.7 g of dimethyl[bromo-(4-chlorophenyl)-methyl]-phosphonate were dissolved in 70 ml oftetrahydrofuran and after cooling to -40° C., over 45 minutes a solutionof 6.16 g of potassium tert-butylate in 60 ml of tetrahydrofuran wasadded. The solution was stirred for 1 hour at -40° C. to -45° C. andthen poured into a saturated aqueous solution of sodium acid phosphate,extracted with isopropyl ether, washed, dried and evaporated to drynessto obtain 18.7 g of the product which was chromatographed on silica andeluted with a mixture of hexane-isopropyl ether (95-5) to obtain 2.97 gof isomer Z (17%). 5.91 g of isomers (E) was also obtained (34.5%).

    ______________________________________                                        NMR Spectrum CDCl.sub.3 60 MHz:                                               ______________________________________                                        (isomere Z)                                                                   aromatic protons      7.16 to 7.68 ppm                                        vinyl protons         5.87 to 6 ppm                                           twinned methyl protons                                                                              1.23 to 1.35 ppm                                        CO.sub.2 --CH.sub.3 protons                                                                         3.7 ppm                                                 protons in position 1 of cyclopropane                                                               1.63 to 1.73 ppm                                        protons in position 3 of cyclopropane                                                               2.35 to 2.56 ppm                                        (isomere E)                                                                   aromatic protons      7.32 ppm                                                vinyl protons         5.85 to 5.98 ppm                                        twinned methyl protons                                                                              1.17 to 1.22 ppm                                        protons in position 1 of cyclopropane                                                               1.52 ppm                                                protons in position 3 of cyclopropane                                                               1.87 to 2.1 ppm                                         ______________________________________                                    

STEP B: Methyl [1R-(1α,3β)]2,2-dimethyl-3-[ΔZ)-2-(4-chlorophenyl)-3,3,3-trifluoro-1-propenyl]-cyclopropanecaraboxylate

2.95 g of methyl [1R-(1α, 3β)]2,2-dimethyl-3-[(ΔZ)-2-bromo-2-(4-chlorophenyl)-ethenyl]-cyclopropanecarboxylate and 4.68 g of sodium trifluoroacetate were dissolved in 30ml of N-methyl-pyrrolidone and 3.27 g of copper iodide were added. Themixture was heated at approximately 160° C. for 6 hours, allowed toreturn to ambient temperature, filtered, rinsed and distilled. Theresidue was extracted with isopropyl ether and the organic phase wasthen washed, dried and evaporated to dryness to obtain 3.94 g of productwhich was chromatographed on silica and eluted by an hexane-isopropylether mixture 95-5 to obtain 2.22 g of the desired product.

    ______________________________________                                        NMR Spectrum CDCl.sub.3 ppm:                                                  ______________________________________                                        twinned methyl proton   1.25 to 1.35 ppm                                      aromatic protons        7.13 to 7.5 ppm                                       ethylenic protons       5.63 to 5.80 ppm                                      carbon protons in position 3 of cyclopropane                                                          2.33 to 2.75 ppm                                      carbon protons in position 1 of cyclopropane                                                          1.69 to 1.78 ppm                                      CO.sub.2 --CH.sub.3 protons                                                                           3.75 ppm                                              ______________________________________                                    

EXAMPLE 2 2-trimethylsilylethyl [1R-(1α, 3β)] 2,2-dimethyl-3-(ΔZ)2-(4-chlorophenyl)-3,3,3-trifluoro-1-propenyl]-cyclopropane carboxylateSTEP A: 2-(trimethylsily) ethyl [1R-(1α,3β)]2,2-dimethyl-3-[(ΔZ)-2-bromo-2-(4-chlorophenyl)-ethenyl]cyclopropane carboxylate and its corresponding E isomer

2.84 g of (1R trans) 2,2-dimethyl-3-formyl-cyclopropane carboxylic acidand 7.5 g of dimethyl [bromo-(4-chlorophenyl)-methyl]-phosphonate weredissolved in 20 ml of tetrahydrofuran and after the solution was cooledto -40° to -45° C., a solution of 5 g of potassium tert-butylate in 25ml of tetrahydrofuran was added over 25 minutes. The solution wasstirred for one hour at -40° to -45° C., then poured into a saturatedaqueous solution of sodium acid phosphate and extracted with isopropylether. The extracts were washed, dried and evaporated to dryness toobtain 7.3 g of residue which was dissolved in 20 ml of methylenchloride.

2.85 ml of trimethylsilyl ethanol were added followed by about 4.53 g ofdicyclohexylcarbodiimide at 0° C., followed by 70 mg of 4-dimethylaminopyridine and 15 ml of methylene chloride. Stirring was carried out for 5minutes in an ice bath and then for one hour at ambient temperature. Themixture was filtered, rinsed with isopropyl ether and evaporated todryness to obtain 9 g of product which was chromatographed with ahexane-isopropyl ether mixture (95-5) to obtain 3.11 g of the desired Zisomer.

    ______________________________________                                        NMR Spectrum CDCl.sub.3 ppm:                                                  ______________________________________                                        aromatic protons       7.15 to 7.52 ppm                                       protons of twinned methyls                                                                           1.24 to 1.37 ppm                                       vinyl proton           5.87 to 6 ppm                                          protons of the carbon in position 3 of the                                                           2.33 to 2.55 ppm                                       cyclopropane                                                                  protons of the carbon in position 1 of the                                                           1.60 to 1.7 ppm                                        cyclopropane                                                                   ##STR32##             4.05 to 4.33 ppm                                        ##STR33##             0.86 to 1.15 ppm                                       1.88 g of E isomer were also obtained.                                        aromatic protons       7.32 ppm                                               protons of twinned methyls                                                                           1.17 to 1.22 ppm                                       vinyl proton           5.87 to 6 ppm                                          protons of the carbon in position 3 of the                                                           1.85 to 2.08 ppm                                       cyclopropane                                                                  protons of the carbon in position 1 of the                                                           1.47 to 1.57 ppm                                       cyclopropane                                                                   ##STR34##             3.96 to 4.25 ppm                                        ##STR35##             0.8 to 1.08 ppm                                        ______________________________________                                    

STEP B: 2-(trimethylsilyl)-ethyl [1R-(1α,3β)]-2,2-dimethyl-3-[(ΔZ)-2-(4-chlorophenyl)-3,3,3-trifluoro-1-propenyl]-cyclopropanecarboxylate

3.06 g of the product of Step A and 3.86 g of sodium trifluoroacetatewere dissolved in 30 ml of N-methyl pyrrolidone and 2.7 g of copperiodide were added. The reaction mixture was held at 160° C. for 6 hours,then allowed to return to ambient temperature, filtered, rinsed and theimpurities were eliminated. After extracting with isopropyl ether, theextracts were diluted with hexane, washed with a saturated solution ofsodium chloride, dried on sodium sulfate and evaporated to dryness toobtain 3.3 g of product which was chromatographed on silica and elutedwith a hexane-toluene mixture 6-4 to obtain 1.69 g of the desiredproduct which was re-chromatographed and eluted with a hexane-isopropylether mixture (95-5) to obtain 1.35 g of the expected product.

    ______________________________________                                        NMR Spectrum CDCl.sub.3 ppm:                                                  ______________________________________                                        aromatic protons        7.08 to 7.42 ppm                                      vinyl protons           5.62 to 5.8 ppm                                       twinned methyl protons  1.22 to 1.32 ppm                                      carbon protons in position 1 of cyclopropane                                                          1.62 to 1.72 ppm                                      carbon protons in position 3 of cyclopropane                                                          2.35 to 2.82 ppm                                      protons α of the CO.sub.2                                                                       4.05 to 4.33 ppm                                      protons β of CO.sub.2                                                                            0.86 to 1.13 ppm                                      ______________________________________                                    

EXAMPLE 3 1-(6-phenoxy-2-pyridyl)-ethyl [1R-[1α(R*),3β]]2,2-dimethyl-3-[(ΔZ)-2-(4-chlorophenyl)-3,3,3-trifluoro-1-propenyl]-cyclopropanecarboxylate

0.85 g of the product of Example 1 were dissolved in 3.75 ml of a normalsodium hydroxide solution and the solution was stirred for 7 hours at40° C. Then it was poured into a mixture of water and ice and, 4 ml of anormal solution of hydrochloric acid were added, followed by washingwith water and with a saturated solution of sodium chloride, drying andevaporation to dryness to obtain 0.84 g of product. The latter wasdissolved with 540 mg of (R)-6-(3-phenoxy)-α-methyl-2-pyridine-methanolin 4 ml of methylene chloride. The mixture was cooled in an ice bath anda solution of 520 mg of dicyclohexylcarbodiimide, 8 mg of4-dimethylaminopyridine and 3 ml of methylene chloride was added. Themixture was stirred for 5 minutes in the ice bath and for one night atambient temperature. The solution was filtered, rinsed with isopropylether and brought to dryness to obtain 1.38 g of product which waschromatographed on silica and eluted with a hexane-isopropyl ethermixture (8-2) to obtain 1 g of the expected product with a specificrotation of [α]_(D) =+98°±2° (c=1%).

EXAMPLE 4 α-Cyano-4-fluoro-3-phenoxy-benzyl[1R-[1α(S*)-3β]-2,2-dimethyl-3-[(ΔZ)2-(4-chlorophenyl)-3,3,3-trifluoro-1-propenyl]-cyclopropane carboxylate

1.32 g of 2-(trimethylsilyl)-ethyl [1R-(1α,3β)]-2,2-dimethyl-3-[(ΔZ)2-(4-chlorophenyl)-3,3,3-trifluoro-1-propenyl]-cyclopropane carboxylateand 6.3 ml of a molar solution of tetrabutylammonium fluoride intetrahydrofuran were stirred for 6 hours at ambient temperature and themixture was poured into a mixture of water and ice. 1.55 ml of a normalsolution of hydrochloric acid were added After extraction with isopropylether, the extracts were washed with a saturated solution of sodiumchloride, dried and evaporated to dryness to obtain 1.1 g of productwhich was added with 780 mg of (S) α-cyano-4-fluoro-3-phenoxy-benzylalcohol to 6 ml of methylene chloride. After cooling in an ice bath, asolution of 650 mg of dicyclohexyl-carbodiimide, 10 mg of4-dimethylamino-pyridine and 4 ml of methylene chloride were added andthe mixture was stirred for 5 minutes at 0°±5° C. then for one hour atambient temperature, followed by filtration, and rinsing with isopropylether to obtain 1.7 g of product. The latter was chromatographed onsilica and eluted with a hexane-isopropyl ether mixture (8-2) to obtain416 g of the expected product melting at 78° C. and having a specificrotation of [α]_(D) =+49°±1.5° (c=1% in CHCl₃).

EXAMPLE 5 1-(6-phenoxy-2-pyridyl)-ethyl [1R-(1α,(RS), 3β]]2,2-dimethyl-3-[(ΔZ)-2-(4-chlorophenyl)-3,3,3-trifluoro-1-propenyl]-cyclopropanecarboxylate

Using the procedure of Example 3, 1.07 g of (RS)6-(3-phenoxy)-β-methyl-2-pyridine-methanol were reacted to obtain 3 g ofproduct which was chromatographed on silica (eluent: hexane-isopropylether 9-1 to obtain 1.97 g of the expected product.

EXAMPLE 6

A homogeneous mixture was prepared from 0.25 g of the product of Example3, 1.00 g of Piperonyl butoxide, 0.05 g of Tween 80, 0.1 g of Topanol Aand 98.4 g of water.

EXAMPLE 7 Preparation of an emulsifiable concentrate

The following were vigorously mixed: 0.015 g of product of Example 4,0.5 g of Piperonyl butoxide, 0.1 g of Topanol A, 3.5 g of Tween 80 and95.885 g of xylene.

EXAMPLE 8 Preparation of an emulsifiable concentrate

The following homogeneous mixture was made: 1.5 g of the Product ofExample 3, 20.0 g of Tween 80, 0.1 g of Topanol A and 78.4 g of xylene.

EXAMPLE 9 Preparation of a fumigant composition

The following were homogeneously mixed: 0.25 g of the Product of Example3, 25.00 g of Tabu powder, 40.00 g of Cedar leaf powder, 33.75 g ofPinewood powder, 0.5 g of Brilliant green and 0.5 g of p-nitrophenol.

EXAMPLE 10

Examples of compositions containing 1700 g of the Product of Example 3,40 ml of Dimethylformamide and 40 ml of Olive oil.

EXAMPLE 11 Preparation of an emulsifiable concentrate

The following were homogenized 0.015 g of the Product of Example 3, 0.5g of Piperonyl butoxide, 0.1 g of Topanol A and 99.385 g of Xylene.

EXAMPLE 12 Preparation of an emulsifiable concentrate

The following homogeneous mixture was prepared: 1.5 g of the Product ofExample 4, 20 g of Tween 80, 0.1 g of Topanol A and 78.4 g of xylene.

BIOLOGICAL STUDY A. Study of lethal activity on the house-fly

The insects tested were four-day old female house-flies and the test wascarried out by topical application of 1 μl of acetone solution on thedorsal thorax of the insects using an Arnold micromanipulator. 50individuals per treatment were used and a mortality check was carriedout 24 hours after treatment. The tests were carried out without asynergist or with the addition of piperonyl butoxide (10 parts ofsynergist per 1 part of test compound). The experimental results, givenin the following table, are expressed in LD 50 (in nanograms) necessaryto kill 50% of the insects:

    ______________________________________                                        Compound of    LD 50                                                          Example        in ng/insect                                                   ______________________________________                                        3              19.6                                                           4              5.3                                                            ______________________________________                                    

B. Study of the lethal effect on Aphis cracivora

7-day old adults were used and 10 aphids per concentration used wereemployed. A contact-injection method was used and the treatment of abroad-bean leaf was carried out with a Fisher gun, the leaf being placedin a plastic Petri dish on a circle of damp paper. The treatment wascarried out with 2 ml of acetone solution of the product under test (1ml per side of leaf). The infestation by the insects was brought aboutafter drying the leaf and the insects were kept in contact with the leaffor one hour. Insects were placed on untreated leaves and the mortalitywas checked after 24 hours. The experimental results obtained are givenin the following table:

    ______________________________________                                        Compound of    LC 50                                                          Example        in mg/l                                                        ______________________________________                                        3              1.34                                                           4              0.6                                                            ______________________________________                                    

C. Study of the acaricide activity in animals

(a) Study of the activity on Boophilus microplus larvae

The substance under test was dissolved in a mixture ofdimethylformamide, emulsifiers and Arcopal so as to obtain a concentrateemulsifying at 10%. This concentrate was diluted with water to obtainsolutions of the desired concentrations of 100, 10 and 1 ppm. Using aspraying tower, the various solutions were sprayed over the larvae oftropical cattle ticks of Boophilus microplus type, and after 24 hours,the percentage of mortality was determined by counting the living anddead larvae. The results are as follows:

    ______________________________________                                                  Results % of mortality                                                        Product of Example                                                  Dose in ppm 3            4      5                                             ______________________________________                                        100         100          100    --                                             10         100          100    100                                            1          100          100    100                                           ______________________________________                                    

Conclusion: the product of Examples 3, 4 and 5 present a remarkableactivity.

(b) Study of the activity on inhibition of the reproduction of Boophilusmicroplus ticks

Boophilus microplus females, ready to lay eggs, were submerged for 5minutes in the solutions prepared above and then they were placed in aheated chamber to lay the eggs. The following were determined: (a) thepercentage of ticks which did not lay eggs, (b) the quantity of eggslaid in relation to a control and (c) the percentage of larvae whichhatched. The percentage of inhibition of reproduction was calculated inrelation to the figures obtained; 100% indicates that inhibition wastotal and 0% that reproduction was identical to that obtained with thecontrols. The following results were obtained:

    ______________________________________                                                  Results % of inhibition                                                       Product of Example                                                  Dose in ppm 3            4      5                                             ______________________________________                                        100         100          100    100                                           50          100          100    100                                           25          100          100    100                                           12.5        100          100    100                                           6.2         100          100    100                                           3.1         100          100    100                                           1.5         100          100    100                                           0.75        100          100    100                                           0.38        100          100     85                                           0.19        100          100    --                                            ______________________________________                                    

Conclusion: The products of Examples 3, 4 and 5 present a remarkableactivity.

Various modifications of the products and processes of the invention maybe made without departing from the spirit or scope thereof and it shouldbe understood that the invention is intended to be limited only asdefined in the appended claims.

What we claim is:
 1. A process for the preparation of atrifluoromethylvinyl compound of the formula (I) in all its possiblestereoisomeric forms or mixtures thereof comprising reacting a salt oftrifluoroacetic acid with a halovinyl compound of formula (II) in thepresence of a cuprous salt to obtain the same stereo-specifictrifluoromethylvinyl compound ##STR36## Z is an electro-attractinggroup, Hal is a halogen, and R is a residue of a pyrethrinoid alcohol oran acid blocking alcohol.
 2. The process of claim 1 wherein the salt ofacetic acid is sodium trifluoroacetate.
 3. The process of claim 1wherein the cuprous salt is cuprous iodide.
 4. The process of claim 1wherein a compound of the formula ##STR37## in all its possiblestereoisomeric forms and mixtures thereof wherein Z is anelectro-attracting group, Hal is bromine, chlorine or iodine and R is aresidue of a pyrethrinoid alcohol or of an acid blocking alcohol isreacted with sodium trifluoroacetate in the presence of cuprous iodideto obtain a compound of the formula: ##STR38##
 5. The process of claim 4wherein Hal is bromine.
 6. The process of claim 4 wherein Z is aryl orhaloaryl.
 7. The process of claim 4 wherein Z is phenyl or4-chlorophenyl.
 8. The process of claim 4 wherein Z is --COOR' and R' isunsubstituted or substituted alkyl of 1 to 8 carbon atoms.
 9. Theprocess of claim 4 wherein R is selected from the group consisting ofalkyl of 1 to 8 carbon atoms, trialkylsilyl alkyl of 1 to 8 carbonatoms, benzyl and benzyl substituted with at least one member of thegroup consisting of alkyl of 1 to 4 carbon atoms, alkenyl and alkenyloxyof 2 to 6 carbon atoms, alkadienyl of 4 to 8 carbon atoms, halogen andmethylenedioxy.
 10. The process of claim 4 wherein R is alkyl of 1 to 4carbon atoms.
 11. The process of claim 4 wherein R is trimethylsilylalkyl of 1 to 4 carbon atoms.
 12. The process of claim 4 wherein R isselected from the group consisting of (a) a group of the formula##STR39## wherein R₁ is hydrogen or methyl and R₂ is monocyclic aryl or--CH.tbd.CH, (b) or a group ##STR40## in which a is hydrogen or methyland R₃ is an aliphatic organic of 2 to 6 carbon atoms having one or morecarbon-carbon unsaturations, (c) or a group ##STR41## in which a ishydrogen or methyl, R₃ has the above definition, R'₁ and R'₂ areindividually hydrogen, halogen, alkyl of 1 to 6 carbon atoms, aryl of 6to 10 carbon atoms, alkoxycarbonyl of 2 to 5 carbon atoms, or cyano, (d)or a group ##STR42## in which B is oxygen or sulfur, ##STR43## or --CH₂-- or a sulfoxide or a sulfone and R₄ is hydrogen, --C.tbd.N, methyl,--CONH₂, --CSNH₂ or --C.tbd.CH, R₅ is halogen or methyl and n is 0, 1 or2, (e) or a group ##STR44## (f) or a group ##STR45## in which R₆, R₇,R₈, R₉ are hydrogen, chlorine, or methyl and which S/I symbolizes anaromatic ring or a dihydro or tetrahydro ring, (g) or a group ##STR46##(h) or a group ##STR47## in which R₁₀ is hydrogen or --CN, R₁₂ is --CH₂-- or oxygen, R₁₁ is thiazolediyl or thiadiazolediyl in which the bondwithcan be found in any of the positions available, R₁₂ is linked to R₁₁by the carbon contained between the sulfur atom and the nitrogen, (i) ora group ##STR48## (j) or a group ##STR49## in which R₁₃ is hydrogen orCN, (k) or a group ##STR50## in which R₁₃ is defined as above, and thebenzoyl radical is in position 3 or 4, (l) or a group ##STR51## in whichone of R₂ " or R₃ " is ##STR52## Z is hydrogen, C.tbd.N, C.tbd.CH, CF₃or alkyl of 1 to 3 carbon atoms and the other R₂ " or R₃ " and R₄ ' andR₅ ' are individually hydrogen, halogen, alkyl of 1 to 18 carbon atoms,aryl of 6 to 14 carbon atoms, arylalkyl of 7 to 18 carbon atoms, cyano,--CF₃, alkoxycarbonyl of 2 to 8 carbon atoms, --NO₂, alkyloxy of 1 to 8carbon atoms. ##STR53## n being 0, 1 or 2 and the radicals Ra, Ra₁ andRa₂ are alkyl of 1 to 8 carbon atoms, Rb is either ##STR54## in which Xand Y are individually hydrogen, halogen, alkyl of 1 to 8 carbon atomsor aryl of 6 to 14 carbon atoms or ##STR55## radical in which X', Y' andY" are individually one of values indicated above for X and Y, thedotted line representing a possible double bond between the carbons 1and 2; (m) or ##STR56## in which r' can have the values indicatedpreviously for R₄ ' and R₅ ' with the exception of halogen, cyano,--NO₂, ##STR57## in which n is either 1 or 2 and ##STR58## (n) or##STR59## , in which R" and R"' are individually hydrogen alkyl of 1 to18 carbon atoms, aryl of 6 to 14 carbon atoms, aralkyl of 7 to 18 carbonatoms, CF₃, alkoxycarbonyl of 2 to 8 carbon atoms or alkoxy of 1 to 8carbon atoms, (o) or a group ##STR60## in which R₁₄ is hydrogen, methyl,ethynyl or cyano and R₁₅ and R₁₆ are individually hydrogen, fluorine orbromine, (p) or a group ##STR61## in which R₁₄ is defined as above, eachof the R₁₇ 's independently is alkyl of 1 to 4 carbon atoms, alkoxy of 1to 4 carbon atoms, alkylthio of 1 to 4 carbon atoms, alkylsulfonyl of 1to 4 carbon atoms, trifluoromethyl, 3,4-methylenedioxy, chloro, fluoroor bromo, p is an integer 0, 1 or 2 and B' is oxygen or sulfur.
 13. Aprocess of claim 1 wherein the final product is selected from the groupconsisting of methyl [1R-(1α, 3β)2,2-dimethyl-3-[(ΔZ)-2-(4-chlorophenyl)-3,3,3-trifluoro-1-propenyl]cyclopropanecarboxylate and 2-(trimethylsilyl)-ethyl [1R-(1α, 3β) 2,2-dimethyl-[-3-[(ΔZ)-2-(4-chlorophenyl)-3,3,3-trifluoro-1-propenyl]-cyclopropanecarboxylate.